A control device for a continuously variable speed change machine disclosed in JP-A-2011-185430 (Reference 1) described below, for example, has been known in the related art. In the related control device, when a sudden speed change is required, an electronic control device calculates an instruction oil pressure obtained by adding a correction value that offsets an oil pressure response delay with respect to a target oil pressure, and outputs a drive command corresponding to the calculated instruction oil pressure to an oil pressure control unit.
In this regard, in the related control device described above, the instruction oil pressure obtained by adding the correction value that offsets the oil pressure response delay is calculated. However, in the related control device described above, in a case where the instruction pressure obtained by adding the correction value is applied at the start of a slip and an actual oil pressure generated in response to the instruction pressure overshoots, heat generation due to excessive slip amount occurs, and complete disengagement and re-engagement of a friction engagement element are repeated and an unnecessary shock occurs.
Thus, a need exists for an oil pressure control device which is not susceptible to the drawback mentioned above.